This project will study the interrelationship of carbohydrate and protein metabolism in subjects with metastatic cancer. Trace amounts of alanine, pyruvate and glucose will be given to patients with metastatic malignant disease to obtain quantitative measurements of new glucose production, gluconeogenesis from amino acids and Cori cycle activity. Concomitant study of glucose uptake and amino acid release from muscle will be done. Such studies will be carried out in the post absorption state, with glucose administration and after long term parenteral administration of glucose and amino acids.